You may take a deduction for certain health insurance premiums on line 18 instead of IA 1040, Schedule A. Your IA 1040, Schedule A cannot contain any health insurance premiums which are used as a deduction on line 18. Typically, health insurance premiums are made on a pre-tax basis when they are deducted from wages. These premiums are not eligible to be claimed on line 18 or IA 1040, Schedule A.